A weighing system is an onboard measurement function that determines the mass of material loaded into a bucket, bed, or body during the normal work cycle, without interrupting operation for a separate weighing step. It is standard equipment on many wheel loaders and excavators used in aggregates, mining, and waste handling, and is increasingly specified on articulated dump trucks and rigid haulers.
Function and Measurement Principle
On wheel loaders and excavators, payload is calculated dynamically while the boom or arm moves through the lift motion. Pressure sensors mounted in the hydraulic lift cylinders record the hydraulic pressure required to raise the load. A separate angle sensor or inclinometer on the boom tracks lift geometry, since the leverage and therefore the required hydraulic force change throughout the lift arc. An onboard controller combines pressure and angle data at defined points of the lift trajectory, filters out dynamic effects such as oscillation and acceleration, and outputs a stabilized weight value once the bucket reaches a consistent reference position.
On dump trucks, the measurement principle depends on the suspension design. Machines with hydro-pneumatic suspension use pressure sensors in the suspension cylinders, comparing pressure in laden and unladen states. Machines with mechanical suspension or rigid mounting points use strain gauge load cells integrated into chassis cross-members or body pivot brackets, measuring the deformation caused by the load.
Sensor Technology
Hydraulic pressure transducers used in lift-cylinder weighing typically measure in the range up to 400–600 bar, matching the working pressure of the loader or excavator hydraulic circuit. Boom angle is captured either by a rotary potentiometer at the pivot pin or by an inclinometer mounted on the boom structure. Strain gauge load cells used in dump truck body or chassis applications convert mechanical deformation into an electrical signal proportional to the applied force.
Accuracy and Calibration
Dynamic weighing accuracy depends on operator technique, lift speed, and calibration state. Systems require periodic calibration with a known reference weight, and most manufacturers specify a tolerance band rather than a single value because accuracy decreases with inconsistent lift motion or uneven ground. Many onboard systems are intended for load optimization and fleet management rather than as certified trade scales, and are not substitutes for static certified weighbridges where legal-for-trade documentation is required.
Applications across Machine Types
On wheel loaders, the weighing system supports truck loading to target payload, reducing both underloading, which wastes cycles, and overloading, which risks fines and accelerated wear. On excavators, the function is used in truck loading operations in quarries and mining where cycle-by-cycle tonnage tracking feeds into production reporting. On articulated and rigid dump trucks, weighing systems monitor payload distribution and total load against the rated capacity, supporting compliance with site overload policies.
Weighing System in Our Coverage
The Liebherr TA 230 Litronic debut at Steinexpo 2026 includes a factory-fitted weighing system that captures payload data in real time during the loading process. Operators view the current load both numerically and via a simplified icon on the in-cab display, supporting precise loading in quarry operation.